US7502006B2 - Method for adjusting electro-optical apparatus, adjusting apparatus of electro-optical apparatus, and electronic system - Google Patents

Method for adjusting electro-optical apparatus, adjusting apparatus of electro-optical apparatus, and electronic system Download PDF

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US7502006B2
US7502006B2 US10/990,604 US99060404A US7502006B2 US 7502006 B2 US7502006 B2 US 7502006B2 US 99060404 A US99060404 A US 99060404A US 7502006 B2 US7502006 B2 US 7502006B2
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image signal
electro
pixel electrodes
potential
optical apparatus
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US20050162365A1 (en
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Toru Aoki
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Seiko Epson Corp
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    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3648—Control of matrices with row and column drivers using an active matrix
    • G09G3/3655—Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3614—Control of polarity reversal in general
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0202—Addressing of scan or signal lines
    • G09G2310/0218—Addressing of scan or signal lines with collection of electrodes in groups for n-dimensional addressing
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0247—Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3685—Details of drivers for data electrodes
    • G09G3/3688—Details of drivers for data electrodes suitable for active matrices only

Definitions

  • Exemplary aspects of the present invention relate to a technique for adjusting a potential (referred to as “common potential”) to be applied to an opposing electrode of an electro-optical apparatus.
  • common potential a potential
  • alternating current drive is adopted in order to prevent the deterioration of the characteristics of the electro-optical material.
  • an active matrix liquid crystal device using a thin film transistor as a switching element
  • an almost constant common potential is applied to an opposing electrode opposed to a plurality of pixel electrodes with a liquid crystal sandwiched.
  • an image signal indicating the content of an image is periodically inverted using a predetermined potential as a reference, and then is supplied to each pixel electrode.
  • an effective voltage value applied to a liquid crystal when the image signal is positive is not necessarily the same as that when the signal is negative.
  • the effective voltage value differs in this manner, a direct current component of a voltage is kept applied to the liquid crystal, thereby causing the deterioration of the characteristics of the liquid crystal.
  • Exemplary aspects of the present invention have been made in view of these and/or other circumstances. Exemplary aspects of the present invention select, in an easy procedure, a common potential which can suppress a flicker while reducing a direct current component applied to an electro-optical material.
  • an electro-optical apparatus which includes: a plurality of pixel electrodes electrically connected to a switching element disposed at each intersection of a plurality of scanning lines and a plurality of data lines; an opposing electrode opposed to the plurality of pixel electrodes with an electro-optical material sandwiched; a scanning-line drive circuit which selects each of the plurality of scanning lines in sequence and turns on the switching element corresponding to the scanning line; and a data-line drive circuit which supplies an image signal, whose polarity is periodically inverted using a predetermined potential as a reference, to the pixel electrode through the data line and the switching element.
  • the electro-optical material in an exemplary aspect of the present invention is a material which changes optical characteristics, such as a transmittance ratio and luminance, by imposing electrical energy, such as a current and voltage.
  • a typical example of the electro-optical material is a liquid crystal which changes the transmittance ratio by the change of molecular alignment direction in accordance with the applied voltage.
  • the range to which the present invention can be applied is not limited to this.
  • An exemplary aspect of the present invention suppresses a direct current component imposed on the electro-optical material.
  • exemplary aspects of the present invention are particularly suitable for an electro-optical apparatus using an electro-optical material which may cause a problem, such as deterioration of optical characteristics due to an imposed direct current component.
  • an exemplary aspect of the present invention provides a method to adjust, the voltage applied to an opposing electrode to a voltage higher than a voltage causing a minimum flicker.
  • this method includes a first step of adjusting a common potential applied to the opposing electrode to a potential at which the variation amount of light emitted from the electro-optical apparatus is minimized in the course of displaying a specific image; and a second step of setting the common potential to a potential higher than the potential adjusted in the first step.
  • the voltage of the opposing electrode may be selected such that the variation amount of the light emitted from the electro-optical apparatus becomes a predetermined value or less. Specifically, it is desirable to select the voltage of the opposing electrode such that the effective voltage value applied to a liquid crystal when the image signal is positive is the same as that of when it is negative.
  • the voltage held between the pixel electrode and the opposing electrode in a horizontal scanning period gradually decreases when the switching element is in an off state (specifically, when the scanning line is not selected). This is because a current leaks from the pixel electrode through the switching element. Meanwhile, at this time, the leakage amount (degree of leakage) of when the image signal is positive may differ from that of when the image signal is negative. Specifically, the leakage amount of when the positive image signal is supplied is larger than that of when the negative image signal is supplied. Accordingly, the variation amount (attenuation amount) per unit time of the voltage held by the pixel electrode when the image signal is positive becomes larger than that of when the image signal is negative.
  • the common potential is selected so as to minimize a flicker, the result is that the effective voltage value to the liquid crystal when the image signal is positive polarity differs from that of when the image signal is negative polarity.
  • the common potential selected in order to minimize a flicker becomes smaller than the potential to eliminate the difference in the effective voltage value to the liquid crystal.
  • a potential higher than the potential which minimizes a flicker is selected as the common potential.
  • the polarity of the image signal is inverted for each specific period, such as a horizontal scanning period and a vertical scanning period.
  • a horizontal scanning period and a vertical scanning period In the structure in which the polarity of the image signal is inverted for each one or a plurality of vertical scanning periods, it is desirable to supply the image signal corresponding to an intermediate grayscale to each of the plurality of pixel electrodes.
  • an intermediate grayscale it is easier to obtain the variation of light emitted from an electro-optical apparatus compared with the cases of the lowest grayscale (black) and the highest grayscale (white).
  • an electro-optical apparatus may adopt a structure (structure which adopts so-called line inversion, column inversion, and pixel inversion) in which a plurality of pixel electrodes are divided into a first group and a second group, and the polarity of the image signal supplied to each pixel electrode is inverted such that the polarity of the image signal supplied to the pixel electrodes included in the first group is the opposite to the polarity of the image signal supplied to the pixel electrodes included in the second group.
  • a structure structure which adopts so-called line inversion, column inversion, and pixel inversion
  • a plurality of pixel electrodes are interchangeably divided into a first group and a second group for one or a plurality of lines of pixel electrodes corresponding to each scanning line, and the image signal having the opposite polarity is supplied to the individual groups of the pixel electrodes.
  • a first step it is desirable to supply the image signal corresponding to an intermediate grayscale to the pixel electrodes of each line included in the first group, and to supply the image signal corresponding to the lowest grayscale to the pixel electrodes of each line included in the second group.
  • a plurality of pixel electrodes are interchangeably divided into a first group and a second group for one or a plurality of columns of pixel electrodes corresponding to each data line. Accordingly, when adjusting the common potential for the electro-optical apparatus having this structure, in a first step, it is desirable to supply the image signal corresponding to an intermediate grayscale to the pixel electrodes of each column included in the first group, and to supply the image signal corresponding to the lowest grayscale to the pixel electrodes of each column included in the second group.
  • a plurality of pixel electrodes are interchangeably divided into a first group and a second group for one or a plurality of the adjacent pixel electrodes in an extension direction (X direction) of the scanning lines and in an extension direction (Y direction) of the data lines.
  • X direction extension direction
  • Y direction extension direction
  • the line inversion, the column inversion, and the pixel inversion have been exemplified.
  • a method for inverting the polarity of the image signal is arbitrary.
  • an exemplary aspect of the present invention can be identified as an apparatus to adjust the common potential in an electro-optical apparatus.
  • an adjusting apparatus including a light receiving device which receives light emitted from the electro-optical apparatus and outputs an electrical signal in accordance with the received light amount; an adjusting device which adjusts a common potential to a potential causing the electronic signal output from the light receiving device to have a minimum amplitude (specifically, in order to minimize the variation amount of light emitted from the electro-optical apparatus); and a setting device which sets the common potential to a potential higher than the potential adjusted by the adjusting device.
  • this adjusting apparatus for the same reason as the adjusting method described above, it is possible to reduce a direct current component applied to the electro-optical material, and to suppress a flicker.
  • a structure which is further provided with a display control device to indicate an image to be displayed to the electro-optical apparatus in the first step, may be adopted.
  • the image content (a grayscale indicated by the image signal) indicated in the electro-optical apparatus with this structure is the same as the example shown for the adjusting method described above.
  • FIG. 1 is a schematic illustrating the configuration of a liquid crystal device according to an exemplary embodiment of the present invention
  • FIG. 2 is a schematic illustrating the structure of the liquid crystal device
  • FIG. 3 is a schematic illustrating the structure on an element substrate 41 of the liquid crystal device
  • FIG. 4 is a timing chart for explaining the operation of the liquid crystal device
  • FIG. 5 is a timing chart illustrating the waveform of the potential of a pixel electrode 413 in the liquid crystal device
  • FIG. 6 is a graph illustrating the relationship between the gate-source voltage of a TFT and the drain current
  • FIG. 7 is a flowchart illustrating the flow of the processing to adjust the common potential of the liquid crystal device
  • FIG. 8 is a schematic illustrating the state of the variation of the amount of light emitted from the liquid crystal device
  • FIG. 9 is a graph illustrating the relationship between the common potential and the variation amount of emitted light.
  • FIG. 10 is a schematic illustrating an image displayed to a liquid crystal device in the adjusting method according to a modification.
  • the polarity inversion circuit 23 performs polarity inversion on the image signals of the six systems, and appropriately amplifies the signals, and then outputs the signals to the liquid crystal panel 4 as image signals VID (VID 1 , VID 2 , . . . , VID 6 ).
  • polarity inversion is processing which interchangeably switches the voltage level of the image signals VID 1 to VID 6 from one to the other of positive polarity and negative polarity using a predetermined voltage Vc as a reference.
  • the image signal VID to be the target of the polarity inversion is appropriately selected in accordance with whether a method of applying a voltage to each pixel is (1) a method of inverting polarity for each vertical scanning period (so-called frame inversion), (2) a method of inverting polarity for each pixel connected to a common scanning line 411 (so-called line inversion), (3) a method of inverting polarity for each pixel connected to a common data line 412 (so-called column inversion), or (4) a method of inverting polarity for each adjacent pixel (so-called pixel inversion).
  • the inversion cycle thereof is set to one dot-clock cycle, one horizontal-scanning period, or one vertical-scanning period.
  • an assumption is made of the case of adopting a method of inverting the polarity of the image signal VID for each vertical scanning period.
  • the liquid crystal panel 4 displays an arbitrary image by a plurality of pixels arranged in a matrix extending in an X direction (line direction) and in a Y direction (column direction).
  • the liquid crystal panel 4 has an element substrate 41 and an opposing substrate 42 , which are bonded opposed to each other through a sealing material 45 formed in nearly a rectangular frame.
  • the space surrounded by both of the substrates and the sealing material 45 is filled with a TN (Twisted Nematic) liquid crystal 46 as an electro-optical material, and is sealed.
  • TN Transmission Nematic
  • n is a natural number of 1 or more data lines 412 , which are extending in a Y direction to be connected to a data-line drive circuit 63 are disposed.
  • 6 n in total of the data lines 412 are divided into n blocks (B 1 , B 2 , . . .
  • a pixel electrode 413 is disposed at each intersection of a plurality of the scanning lines 411 and a plurality of the data lines 412 .
  • Each pixel electrode 413 is an almost rectangular electrode opposed to the opposing electrode 421 sandwiching the liquid crystal 46 , and is electrically connected to a thin film transistor (in the following, referred to as a TFT (Thin Film Transistor)) 414 disposed at the intersection between the scanning lines 411 and the data lines 412 .
  • a TFT Thin Film Transistor
  • the pixels which are constituted by the pixel electrode 413 , the opposing electrode 421 , and the liquid crystal 46 sandwiched between both of the electrodes, are arranged in a matrix state extending in an X direction and in a Y direction.
  • the liquid crystal panel 4 according to the present exemplary embodiment is a so-called normally-white mode panel, in which the display grayscale of the pixel is the brightest (white display) when the voltage applied to the liquid crystal 46 is at a minimum, and the display grayscale of the pixel gradually becomes darker as the voltage increases.
  • the scanning-line drive circuit 61 is a circuit which selects each of the m scanning lines 411 in sequence under the control of the control circuit 1 .
  • the scanning-line drive circuit 61 turns scanning signals G 1 , G 2 , . . . , Gm supplied to each of the m scanning lines 411 to an active level (H level) in sequence for each horizontal scanning period.
  • a scanning signal Gi i is a natural number from 1 to m
  • one line of the TFTs 414 connected to the scanning line 411 are simultaneously turned on.
  • each image signal VID is positive in this vertical scanning period
  • the polarity of each image signal VID is set to negative in the next vertical scanning period.
  • FIG. 5 is a timing chart illustrating the state of the change of the driving potential Vpix. In the figure, the case where an intermediate grayscale (gray) is displayed by the pixels including this pixel electrode 413 is assumed.
  • the scanning signal Gi changes from a non-active level (the lower potential Gnd of the power source) to an active level (higher potential Vcc) and the TFT 414 is turned on
  • the potential Vgp in accordance with the positive image signal VID corresponding to an intermediate grayscale is applied to the pixel electrode 413 as a driving potential Vpix.
  • This driving potential Vpix is maintained during the period (referred to as a “non-selected period”) from the time when the scanning signal Gi changes to a non-active level and the TFT 414 is turned off to the time when the scanning signal Gi changes to an active level in the next horizontal scanning period H 2 .
  • the reason why the driving potential V decreases in a moment at the timing of the change of the scanning signal Gi to a non-active level as shown in the figure is that the effect of the variation of the scanning signal Gi extends the drain potential of the TFT 414 (so-called push down occurs) due to the occurrence of parasitic capacitance between the gate and the drain of the TFT 414 .
  • the potential Vgn in accordance with the negative image signal VID corresponding to an intermediate grayscale is applied to the pixel electrode 413 as a driving potential Vpix, and is maintained during the subsequent non-selected period.
  • the driving potential Vpix applied to the pixel electrode 413 is maintained during the non-selected period by the capacitance constituted by the pixel electrode 413 and the opposing electrode 421 .
  • the driving potential Vpix maintained in the pixel electrode 413 is attenuated with the elapse of time in the non-selected period. As shown in FIG.
  • the degree (the variation amount per unit time) of attenuation of the driving potential Vpix is different from the case where a positive image signal VID is supplied to the pixel electrode 413 (referred to as “positive polarity write time”) and the case where a negative image signal VID is supplied (referred to as “negative polarity write time”).
  • positive polarity write time the case where a positive image signal VID is supplied to the pixel electrode 413
  • negative polarity write time referred to as “negative polarity write time”.
  • FIG. 6 is a graph illustrating the relationship between the gate-source voltage Vgs of the TFT 414 and the source-drain current Id of the TFT 414 .
  • the source-drain current Ip flows, and the driving potential Vpix is maintained in the pixel electrode 413 .
  • the gate-source voltage Vgs is negative
  • the source-drain current Id also flows through TFT 414 .
  • the TFT 414 is an element formed on the plate surface of the element substrate 41 by a polysilicon process, this tendency becomes especially remarkable.
  • the gate-source voltage Vgs of the TFT 414 connected to that pixel electrode 413 corresponds the difference between the lower potential Gnd and the potential (Vgp or Vgn) of the image signal VID supplied to another pixel electrode 413 through the data lines 412 . Accordingly, as shown in FIG.
  • the voltage Vp applied between the gate and the source of the TFT 414 in the vertical scanning period when the positive image signal VID is supplied to the data lines 412 the voltage Vp applied between the gate and the source of the TFT 414 becomes smaller (the absolute value becomes large) than the voltage Vn applied between the gate and the source of the TFT 414 in the vertical scanning period when the negative image signal VID is supplied.
  • the gate-source voltage Vgs when the gate-source voltage Vgs is negative, the smaller this voltage Vgs, the larger the leakage current Id becomes. Accordingly, the leakage current Ip at positive polarity write time becomes larger than the leakage current In at negative polarity write time.
  • the variation amount per unit time (attenuation amount) of the driving potential Vpix maintained in the pixel electrode 413 at positive polarity write time becomes larger than that at negative polarity write time.
  • a potential Vcom which is selected such that the effective voltage value (the area of an area S 1 ) applied to the liquid crystal 46 at positive polarity write time is equal to the effective voltage value (the area of an area S 2 ) applied to the liquid crystal 46 at negative polarity write time, and a potential Vcom′ selected to minimize a flicker are shown.
  • the potential Vcom′ is smaller than the potential Vcom.
  • the common potential LCcom applied to the opposing electrode 421 is set to a potential V 0 higher than the potential Vcom′ which minimizes a flicker.
  • FIG. 7 is a flowchart illustrating the flow of the processing to adjust the common potential LCcom.
  • step S 1 displaying a specific image is instructed to the liquid crystal device 100 (step S 1 ).
  • an assumption is made that the polarity of the image signal VID is inverted for each vertical scanning period.
  • an instruction is given to all the pixels to display an intermediate grayscale in the step S 1 .
  • the reason why the display grayscale is set to an intermediate grayscale is that a very little variation of the amount of light emitted from the liquid crystal device 100 appears more remarkably for an intermediate grayscale compared with black color or white color. Thus it is easier for the operator to view this.
  • the common potential LCcom of the liquid crystal device 100 is adjusted so as to minimize a flicker of the display screen (step S 2 ). That is to say, the operator adjusts the common potential LCcom by appropriately operating the operation element (omitted in the figure) of the liquid crystal device 100 while viewing the display image, and stops the adjustment when the flicker becomes the minimum. Thus the common potential LCcom is adjusted to the potential Vcom′ described above.
  • FIG. 8 is a schematic illustrating the time-series variation of the amount of light emitting from the liquid crystal device 100 .
  • the variation A shown in the figure is a parameter indicating the degree of a flicker, and is defined as a difference between the maximum value Lmax and the minimum value Lmin of the amount of the emitted light.
  • this variation amount A has a minimum value when the common potential LCcom is equal to the potential Vcom′ described above, and increases as the common potential LCcom is apart from the potential Vcom′.
  • the operator appropriately adjusts the common potential LCcom while viewing the display image, and adjusts the common potential LCcom to the potential Vcom′ so as to minimize this variation amount A.
  • step S 1 of FIG. 7 it is desirable to interchangeably display an intermediate grayscale and the lowest grayscale (specifically, the grayscale corresponding to black) for each adjacent line with each other as shown in FIG. 10 .
  • the image signal VID corresponding to an intermediate grayscale is supplied to the pixel electrode 413 connected to the scanning lines 411 which are odd-numbered when counted from the top of the display area.
  • the image signal VID corresponding to black is supplied to the pixel electrode 413 connected to the even-numbered scanning lines 411 .
  • a plurality of pixel electrodes 413 are divided into two groups, each of which includes the pixel electrodes 413 having the common variation mode of the polarity of the image signal VID (for example, the pixel electrodes 413 to which the positive image signal VID is supplied in a certain vertical scanning period are put together into a first group, and the pixel electrodes 413 to which the negative image signal VID is supplied in the same vertical scanning period are put together into a second group).
  • a liquid crystal device 100 specifically, a device adopting pixel inversion which inverts the polarity of the image signal VID for each of the pixel electrodes 413 adjacent in an X direction or a Y direction
  • a liquid crystal device 100 which inverts the polarity of the image signal VID for the pixel electrodes 413 of each column corresponding to a data line
  • it is desirable to display the image specifically, the image in which the intermediate grayscale lines and the lowest grayscale lines which extend in a Y direction are arranged in a stripe state
  • the intermediate grayscale and the lowest grayscale are interchangeably arranged for the pixel electrodes 413 of each column.
  • this adjusting apparatus includes a light receiving circuit (for example, a CCD (Charge Coupled Device)) which outputs an electrical signal in accordance with the amount of light received from the liquid crystal device 100 ), an adjusting circuit which adjusts the common potential LCcom to the potential Vcom′ such that the amplitude (specifically, the variation amount A of light emitted from the liquid crystal device 100 ) of the electrical signal from this light receiving circuit is minimized, and a setting circuit which sets the common potential LCcom to a potential V 0 higher than the adjusted value Vcom′ by the adjusting circuit.
  • a light receiving circuit for example, a CCD (Charge Coupled Device)
  • Vcom′ the adjusting circuit which adjusts the common potential LCcom to the potential Vcom′ such that the amplitude (specifically, the variation amount A of light emitted from the liquid crystal device 100 ) of the electrical signal from this light receiving circuit is minimized
  • a setting circuit which sets the common potential LCcom to a potential V 0 higher than the adjusted value Vcom
  • This adjusting apparatus may be a separate apparatus from the liquid crystal device 100 .
  • the apparatus may be partly or wholly included in the liquid crystal device 100 (for example, an apparatus whose adjusting circuit and setting circuit are contained in the control circuit 1 of FIG. 1 ).
  • adjusting the common potential LCcom to the potential Vcom′ and adjusting the common potential LCcom to a higher potential V 0 may also be achieved by the execution of a program by a computer with an operation unit such as a CPU, or the like, for example.
  • a filter circuit which selectively passes only a component included in a specific frequency band (for example, a frequency band of about 30 Hz, which especially causes a problem of a flicker) out of the electrical signal output from the light receiving circuit, may be provided.
  • a specific frequency band for example, a frequency band of about 30 Hz, which especially causes a problem of a flicker
  • the device to be the target, in which the common potential LCcom is adjusted by the adjusting method according to an exemplary aspect of the present invention is not limited to a liquid crystal device using a liquid crystal as a electro-optical material.
  • Exemplary aspects of the present invention suppress a direct current component for an electro-optical material.
  • Exemplary aspects of the present invention therefore, may be used for an electro-optical apparatus using an electro-optical material which might cause a problem, such as deterioration of the characteristics by the application of a direct current component.

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  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
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US10/990,604 2003-11-27 2004-11-18 Method for adjusting electro-optical apparatus, adjusting apparatus of electro-optical apparatus, and electronic system Expired - Fee Related US7502006B2 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070139343A1 (en) * 2005-12-16 2007-06-21 Innolux Display Corp. Liquid crystal display panel with photo sensors and method for adjusting reference voltage in the panel

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI357046B (en) * 2006-10-24 2012-01-21 Novatek Microelectronics Corp Method for driving lcd monitors
CN101393726B (zh) * 2007-09-21 2011-02-02 北京京东方光电科技有限公司 像素灰度扩展方法、像素电容充电时间驱动方法及装置
JP5487585B2 (ja) * 2008-09-19 2014-05-07 セイコーエプソン株式会社 電気光学装置、その駆動方法、および電子機器
EP2169656A1 (en) * 2008-09-24 2010-03-31 Harman Becker Automotive Systems GmbH Liquid crystal display control system
WO2011024338A1 (ja) * 2009-08-28 2011-03-03 シャープ株式会社 液晶表示装置およびその電位設定方法
CN101739993B (zh) * 2010-01-04 2012-06-27 青岛海信电器股份有限公司 公共电极基准电压的调整方法和装置
JP5512788B2 (ja) * 2010-02-17 2014-06-04 シャープ株式会社 液晶表示装置の表示検査方法
CN101783125A (zh) * 2010-03-04 2010-07-21 青岛海信电器股份有限公司 基准电压调整装置与方法及液晶显示器
CN102621750B (zh) * 2011-01-28 2015-02-04 华映科技（集团）股份有限公司 一种用于提升液晶面板显示质量的方法
CN103439814B (zh) * 2013-09-04 2015-11-11 深圳市华星光电技术有限公司 液晶显示装置残像改善方法及装置

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08286169A (ja) 1995-04-19 1996-11-01 Nec Corp 液晶表示装置の対向電極調整回路
US5774106A (en) * 1994-06-21 1998-06-30 Hitachi, Ltd. Liquid crystal driver and liquid crystal display device using the same
JPH10268259A (ja) 1997-03-26 1998-10-09 Advanced Display:Kk 液晶表示装置の駆動方法
US6342876B1 (en) * 1998-10-21 2002-01-29 Lg. Phillips Lcd Co., Ltd Method and apparatus for driving liquid crystal panel in cycle inversion
JP2002182623A (ja) 2000-10-04 2002-06-26 Seiko Epson Corp 画像信号補正回路、その補正方法、液晶表示装置及び電子機器
JP2002182622A (ja) 2000-10-04 2002-06-26 Seiko Epson Corp 画像信号補正回路、その補正方法、液晶表示装置及び電子機器
JP2002229529A (ja) 2000-12-01 2002-08-16 Seiko Epson Corp 液晶表示装置、画像データ補正回路、画像データ補正方法および電子機器
US6593921B2 (en) * 2000-01-18 2003-07-15 Kabushiki Kaisha Advanced Display System and method for adjusting image quality of liquid crystal display
JP2004062189A (ja) 2003-07-22 2004-02-26 Canon Inc 走査光学装置及び画像形成装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08334741A (ja) * 1996-06-24 1996-12-17 Seiko Epson Corp 液晶装置
JP3632637B2 (ja) * 2001-08-09 2005-03-23 セイコーエプソン株式会社 電気光学装置、その駆動方法、電気光学装置の駆動回路および電子機器
JP3906665B2 (ja) * 2001-10-05 2007-04-18 カシオ計算機株式会社 液晶駆動装置

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5774106A (en) * 1994-06-21 1998-06-30 Hitachi, Ltd. Liquid crystal driver and liquid crystal display device using the same
JPH08286169A (ja) 1995-04-19 1996-11-01 Nec Corp 液晶表示装置の対向電極調整回路
JPH10268259A (ja) 1997-03-26 1998-10-09 Advanced Display:Kk 液晶表示装置の駆動方法
US6342876B1 (en) * 1998-10-21 2002-01-29 Lg. Phillips Lcd Co., Ltd Method and apparatus for driving liquid crystal panel in cycle inversion
US6593921B2 (en) * 2000-01-18 2003-07-15 Kabushiki Kaisha Advanced Display System and method for adjusting image quality of liquid crystal display
JP2002182623A (ja) 2000-10-04 2002-06-26 Seiko Epson Corp 画像信号補正回路、その補正方法、液晶表示装置及び電子機器
JP2002182622A (ja) 2000-10-04 2002-06-26 Seiko Epson Corp 画像信号補正回路、その補正方法、液晶表示装置及び電子機器
JP2002229529A (ja) 2000-12-01 2002-08-16 Seiko Epson Corp 液晶表示装置、画像データ補正回路、画像データ補正方法および電子機器
JP2004062189A (ja) 2003-07-22 2004-02-26 Canon Inc 走査光学装置及び画像形成装置

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070139343A1 (en) * 2005-12-16 2007-06-21 Innolux Display Corp. Liquid crystal display panel with photo sensors and method for adjusting reference voltage in the panel
US7800603B2 (en) * 2005-12-16 2010-09-21 Chimei Innolux Corporation Liquid crystal display panel with photo sensors and method for adjusting reference voltage in the panel

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